The movie revolves with the unwanted incedents happened in princly state Ratnagarh. After the murder of the king Chandrakanta, one Dr. Palit (Kamal Mitra) asked for help to one Detective Smarajit Sen (Shisir Batabyal), as a family friend. Detective Sen sent his assistant Bimal to Ratnagarh to investigate and ascertain the security of young Kumar Bahadur, new predecessors of the royal family of the estate. They observed that a mysterious lady Manjusri (Manju De) sing uncanny song in the adjacent water body near the palace. Mr Gupta (Bikash Roy), a suspicious botanist stayed in the neighbourhood also roamed in that locality. It revealed that he was deprived of real property of the royal family and took revenge by killing the members of the family. He used one deaf and dumb porter as a hired killer. Ultimately he has been killed by the detective at the end before he could commit another murder.